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Help with PT4115, ESOP8 LED dimming

According to the Data sheet for the chip PT4115 there are two versions, SOT89-5 AND ESOP8.

Data sheet: http://www.micro-bridge.com/data/CRpowtech/PT4115E.pdf

The information on the sheet says that the DIM pin will accept a PWM signal or an analog signal from 0 up to 2.5 volts, anything over 2.5 volts to 6 volts max will hold the regulator at 100% output. Less than .3 volts will turn off the regulator. It says that there is an internal 200kohm pull up resister connected to 5 Volts, the voltage of DIM pin is divided by the internal and external resistor. I’ve been using Google (as requested) to research PWM but I’m still not sure how to generate the signal. I’m interested in more information regarding the analog option.

This link: http://club.dx.com/forums/forums.dx/threadid.963272 is to another forum where someone had the SOT89-5 version and connected a 200k pot between the DIM pin and Gnd. Their test was successful but had some issues with flickering due to lack of power.

Questions:
What’s the better of the two dimming options?

If I continue with the analog option, will I need unsolder the pin from the purchased LED Driver board (board configured for 100% output) and then connect to analog signal? In the image on the other forum it seems like they just soldered a wire on to existing configuration.

Will the ESOP8 version react in the same manner as the SOT89-5?
 
Hi,

If the dim pin accept both analog voltage or PWM i guess that some sort of integration is done internally.

PWM is more adapted to uC interfacing, and analog is pretty easy for manual control, that's it.

Both package should react the same way, only power dissipation capabilities can vary.

Olivier
 
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